Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field.
Oscillating coils, particularly Tesla coils and Magnifiers have long since been used to produce high AC voltages and currents. A typical Tesla coil has an impedance of some 50,000 Ohms, however the earth impedance at certain frequencies may approach zero. This represents a very poor impedance match for the Tesla coil or any other oscillating coil that is trying to get decent power transfer to the earth since virtually all power is returned to the transmitter in the return phase due to lack of load resistance. It is important that the transmitter coil and the load must have the same impedance for the efficient transfer of power into the load in conductively connected apparatus, in this case, into the ground as a conduit between the transmitter and the load with the total impedance in the load plus ground impedance equalling the impedence in the transmitter coil. The result of this is that transmission of energy through the ground using these devices has been limited in range as the path of least resistance for the return current is to the coil itself. It is simply impossible to get power into the ground using grounded coils since at the point of power injection to the ground the voltage is virtually zero and since Power=VI very little power transfer takes place. Transmission is overcome by reverse currents forming as there is no voltage to speak of to drive the currents further though the ground. The current and voltage are also out of phase where these coils are traditionally earthed, at the bottom of the coil and this makes the power transfer even more difficult.
In the conventional connection, the coil is connected to the earth at one end so the impedance in the coil capacitor pair would normally have to be matched for transmission to take place efficiently the same as applies to radio which is impossible with existing coil design since for efficient transfer the impedance of the load should equal the impedance of the transmitter thus if we have an impedance of zero we can get no power into the transmitter when the apparatus is operated using the current paradigm.
It would be a great advance in this area of endeavour if a suitable earthing system could be devised for Tesla coils or Magnifiers in particular, but also oscillating coils in LC or LCR systems in general to allow the energy transfer of the current and voltage transmitted between two or more locations on the earth to be efficient and in phase.
Nikola Tesla in his U.S. Pat. No. 645,576 issued 20 Mar. 1900 disclosed a system and method for transmitting electrical energy through a natural media. In particular forms, the propagation of electrical energy is by conduction through air strata however the disclosure of this patent contemplates adjustment of at least frequency and voltage with a view to adjusting the extent to which electrical energy is passed through the air or through the earth. The specification and drawings of U.S. Pat. No. 645,576 are incorporated herein in their entirety by cross reference.
Broadly, the Tesla system comprised a step up transformer arrangement in electrical communication with an earth terminal and an ‘elevated’ terminal. When referenced in later art—for example see U.S. Pat. No. 7,960,867 issued 14 Jun. 2011 to Issa et al, this arrangement is collectively termed the emitter. The step up coil arrangement is also termed a Tesla coil or a Tesla resonator. The emitter transmits electrical energy wirelessly through media including earth and earth's atmosphere to a receiver which comprises a second Tesla resonator or step down arrangement in communication with an earth terminal and an ‘elevated’ terminal.
Attempts continue to this day to transfer efficiently substantial amounts of electrical energy wirelessly broadly in accordance with this mechanism.
In that regard, for example, U.S. Pat. No. 7,960,867 referred to above, issued to Issa et al discloses a particular arrangement for a transmitter and emitter. The entire disclosure of U.S. Pat. No. 7,960,867 is incorporated herein by cross reference and including the prior art references referred to therein.
An unverified report from AFP (Agence France-Presse) dated in 2008 indicates that Intel powered a 60 Watt light bulb utilising a wireless energy resonant link reliant primarily on magnetic field leakage rather than electric field leakage. This approach using substantially entirely induction has severe transmission distance limitations.
It is an object of the embodiments of the present invention to provide a system for wireless distribution of power which addresses or ameliorates one or more of the above mentioned disadvantages.
Notes
The term “comprising” (and grammatical variations thereof) is used in this specification in the inclusive sense of “having” or “including”, and not in the exclusive sense of “consisting only of”.
The above discussion of the prior art in the Background of the invention, is not an admission that any information discussed therein is citable prior art or part of the common general knowledge of persons skilled in the art in any country.